LED EXTERIOR BULB REPLACEMENTS
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From: North Country
There is confusion here. Load resistor is an ambiguous term here...
You need (for 928 rear lighting) 2 types of resistors to use a standard LED in the 12v system:
1) A resistor in series to limit the current (else the LED will burn out).
Most (all?) replacement bulb style LED's include this - and that is what the manufacturer is telling you.
2) A resistor in parallel to keep the bulb control (warning) unit happy. This is what Ed was talking about, and what is in his photo's. Many/most cars don't need this - but a 928 does (or a modified/bypassed bulb control unit).
The parallel resistor can be a single resistor for several bulbs if they are all in parallel (e.g. markers). You only need this for the brakes & rear markers (you need a value to look like the bulbs being replaced). I don't think you will find any LED's with this integrated.
Alan
You need (for 928 rear lighting) 2 types of resistors to use a standard LED in the 12v system:
1) A resistor in series to limit the current (else the LED will burn out).
Most (all?) replacement bulb style LED's include this - and that is what the manufacturer is telling you.
2) A resistor in parallel to keep the bulb control (warning) unit happy. This is what Ed was talking about, and what is in his photo's. Many/most cars don't need this - but a 928 does (or a modified/bypassed bulb control unit).
The parallel resistor can be a single resistor for several bulbs if they are all in parallel (e.g. markers). You only need this for the brakes & rear markers (you need a value to look like the bulbs being replaced). I don't think you will find any LED's with this integrated.
Alan
Yes, I understood this. I wanted to be sure that my replacement bulbs had resistance integrated within it. The extra resistor will be integrated into the turn signal circuit to allow appropriate function as described by Ed. I had already bypassed the Lampkontroller for I had put LED's in the sidemarkers a while back for energy conservation, but left the other incandescents in otherwise. Once I change them all, I'll put a resistor in parallel and plug the two pins back into the Lampkontroller connector.
Add: I also disabled the brake light controller for I had installed a third brake light flasher, and the Lampkontroller didn't like the resultant asymmetry.
Last edited by MainePorsche; Aug 20, 2015 at 01:59 PM.
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From: Shawnee, KS, USA
The only other resistor you'll need related to exterior lighting is—if you're going to convert all of your brake lamps to LEDs, including the CHMSL—a 6 Ω resistor somewhere in the brake light circuit to preserve cruise control functionality. There's a rather lengthy exploration of this topic in the thread Cruise Control Mod for LED Brake Lights; the executive summary, though, is "just use a 6 Ω resistor."
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From: North Country
Not needed. A 25 Ω resistor at each of the two rear turn signal circuits will do the trick.
The only other resistor you'll need related to exterior lighting is—if you're going to convert all of your brake lamps to LEDs, including the CHMSL—a 6 Ω resistor somewhere in the brake light circuit to preserve cruise control functionality. There's a rather lengthy exploration of this topic in the thread Cruise Control Mod for LED Brake Lights; the executive summary, though, is "just use a 6 Ω resistor."
The only other resistor you'll need related to exterior lighting is—if you're going to convert all of your brake lamps to LEDs, including the CHMSL—a 6 Ω resistor somewhere in the brake light circuit to preserve cruise control functionality. There's a rather lengthy exploration of this topic in the thread Cruise Control Mod for LED Brake Lights; the executive summary, though, is "just use a 6 Ω resistor."
According to borland I think I may have the cruise control remedy already in place. I am going to leave the third brake light as an incandescent. borland states the cruise amplifier sources the amplifier's ground through a bulb filament. It's current is very low. When brakes applied this 'ground' is lost thereby defeating the cruise.
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According to borland I think I may have the cruise control remedy already in place. I am going to leave the third brake light as an incandescent. borland states the cruise amplifier sources the amplifier's ground through a bulb filament. It's current is very low. When brakes applied this 'ground' is lost thereby defeating the cruise.
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Nordschleife Master
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From: North Country
Thread Starter
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From: North Country
Was easy. On my MY on the WD there were two pins with words in German. Went to the babylon translator on google and they basically told me that those were the male pins to pull out of the controller connector. If I remember correctly the brake bulb warning kill was to remove pin 7.
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Speed,
Was easy. On my MY on the WD there were two pins with words in German. Went to the babylon translator on google and they basically told me that those were the male pins to pull out of the controller connector. If I remember correctly the brake bulb warning kill was to remove pin 7.
Was easy. On my MY on the WD there were two pins with words in German. Went to the babylon translator on google and they basically told me that those were the male pins to pull out of the controller connector. If I remember correctly the brake bulb warning kill was to remove pin 7.
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From: North Country
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From: Shawnee, KS, USA
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How about...
I found my S3 bulb control module.
But unplugged, and no harness that I can find anywhere near it....???
85 S3.
Gonna be hard to 'fix it' if it is not even wired..
I found my S3 bulb control module.
But unplugged, and no harness that I can find anywhere near it....???
85 S3.
Gonna be hard to 'fix it' if it is not even wired..
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From: Bloomfield, MI
I'm thinking it has already been jumper-ed out.
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Drove the car to work today...and I get the appropriate warnings if I put LEDs where the system wants to see more load.
So...wtf?